Key Differences Between Dental Caries and Dental Erosion

Generalities can be confusing. Caries is often described as the loss of minerals by the direct action of acids on the teeth, and dental erosion is also defined in a similar way. While both statements are true, of primary importance is the type of acid, where the acid comes from and specific sites on the tooth surface to which these acids are directed. It is important to differentiate enamel damage due to caries vs. damage that results from dental erosion. Both the etiology and symptoms of these two processes differ significantly, as do the appropriate management strategies for each (Table 3).

One major difference between caries and dental erosion needs to be clearly understood. Caries is a process that begins with demineralization and, at early stages, can be reversed, either through the natural process of remineralization or through enhanced remineralization due to fluoride therapy. Dental erosion, on the other hand, is essentially a non-reversible process that results in permanent damage to the tooth structure.

Table 3. Key Differences Between Caries and Dental Erosion.

Key Comparisons	Cavities	Erosion
Type of process	Mineral Change	Mineral Loss
Tooth site(s) affected	Enamel & dentin	Enamel & dentin
Primary cause	Bacterial acids	Dietary acids
Primary site(s) of damage	Subsurface, under plaque	Exposed, plaque free surface
Conditions	Exposure to weak acids for prolonged periods of time, usually at a pH above 4.0	Repeated exposure to dietary or gastric acids, generally below pH 4.0, for short time periods
Result	Sub-surface phenomenon with intact outer layer of enamel	Surface softening leading to loss of surface mineral
Reversible?	Reversible in early stages	Irreversible surface loss
Contributing factors	Buffering by saliva helps neutralize bacterial acids	Saliva and pellicle overwhelmed by dietary and gastric acids
Preferred therapeutic approach	Prevention as well as reversal of early damage	Prevention is critical for managing
Fluoride effectiveness	------------	------------
Sodium fluoride	Yes	Yes
Sodium monofluorophosphate	Yes	Minimal
Stannous fluoride	Yes	Yes